Is Sony Working On The PS4K?

The Rumour mill has it that Sony is working on a 4K- version of the PS4 with increased GPU to give in game visuals a boost and will also help the PS VR

Known as the "PS4.5" or "PS4K", developers told Kotaku that the device would feature an improved graphical processing unit (GPU), which would give in-game visuals a boost.

The increased processing power would also let it display games at 4K resolution.

It's worth taking this with a pinch of salt at the moment and it's unlikely to be released this year "if at all" with sources saying it's "exploratory" according to Kotaku. Sony certainly isn't talking about it publicly, although there's murmurs of hush hush meetings.